Industrial truck



E. H. REMDE INDUSTRIAL TRUCK Filed July 4, i924 4 sheets-sheet 1 www@ Wh. Nw

Fw eww wN E. H. REMDE INDUSTRIAL TRUCK Filed July 4,' 1924 4 Sheets#Sheet 2 ArroR/vfx Dec. 24, 1929. E. H. REMDE INDUSTRIAL TRUCK Filed July 4, 1924 4 Sheets-Sheet vw Q mv K l. v x k i ihk www W m A m www :igt l wx W. 7 m N A 9 uw MMMW DCCV24, 19249. E. H REMDE 1,740,712

INDUS TRI AL TRUCK Ffizled July 4, 1924 V4 Sheets-Sheet 4 A A. Wf/yrae Patented tDec. .24, 1929 narran STATESv` ,PATENT OFFICE- EDWARD H. RENDE, OF CLEVELAND, OHIO, ASSIGNOR 'IO THE BAKER-RAULANG- COM P'ANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO INDUSTRIAL TRUCK Application ed .Tillyl 4, 1924. Serial N o. 724,175.

This invention relates to an industrial truck capable of engaging, lifting, transporting and loading and unloading goods,

, bodies and sheet material.

' rig. e.

One object of the invention is to provide a truck of this character that is relatively simple in construction but durable and eiiicient in operation.

Another object of the invention is -to provide an improved construction in which the trailing wheels may be disposed in line with `the traction wheels and at the same time provide ample room for the swinging of the trailing wheels for steeringpurposes.`

Another object of the invention is to provide a relatively simple mounting for the trailing wheels whereby the cost of manufacture and assembly is reduced.

lAnother object of the invention is to provide an Aimproved braking or retardingl means for one of the motors arranged to operate automatically.

Other objects of the invention will be apparent to those skilled in the artto which my invention relates from the following description taken'in connection with the accompanying drawings.

Fig. l is a' side elevation of a truck embodying my invention., parts being broken away to facilitate the illustration.

Fig. 2 is an end elevation looking toward the left of Fig. l.

Fig. 3 is a view similar to Fig. 2, but showing the elevating member in raised position.

Fig. 4 is a plan view of the truck.

Fig. 5 isa section on the linee-5 of Fig. 6 is a fragmentary section'on the line 6-6 of Fig. 3'.

Fig. 7 is a plan view on the line 7-'Z of Fig.

Fig. 8 is a fragmentary section on the ,line

' 8-8 of Fig. 1,-.

Fig. 9 is a section on the line 9 9 of Fig. l0.

Fig. l() is view partly'in plan and partly in section on the line 10-10 of Fig.. 9.

ln the drawings, l' indicates as an entirety a frame of any desirable construction, but

members l, l", l? and 1b may be formed' from channelbars and the members' lb, lb, l",

are preferably formed from a single sectionl of channel bar, the opposite ends of which are connected to the channel bars l by angle plates le (see Fig. 4). The frame members lb and 1b may be connected together by plates 2, secured thereto by rivets, or other suitable means.

3 indicates a pair of traction wheels', preferably mounted on knuckles 3, whereby the wheels may be turned for steering purposes..

As shown in Fig. 4, the frame members 1b,

lb', extend laterally beyond the wheels 8 to form a guard to protect them. 4 indicates the axle casing for an axle mechanism, which may be of any well ,known construction, connected with the spindles for the wheels 3, whereby they are driven. The casing 4 includes a supplemental casing4a for a propeller shaft, which is connected in any de sired manner to the armature shaft of -an electric motor 5f, and a cradle 4b, to whichthe .motor .is rigidly connected. 6 indicates as an entirety a suspension mechanism for the motor 5 and axle casings 4, 4a, and cradle 4b, such mechanism including an element 6a pivoted to the supplemental casing 4a and a transverse rod or shaft 6b supported by the longitudinal frame member la (see Fig. 4) and an element 6 pivoted to the extended end 4" of the cradle 4b and to'a pair of plates 6d depending from the frame members la.

As this suspension mechanism forms the subject-matter of a co-pending application (see Letters Patent No. 1,628,145), no claim is made thereto in this application and for the same reason further description herein will not be necessary.

7 indicates a pair of spaced, vertically arranged-members, preferably comprising I- l beams, disposed at and connected to that end ,guides 7 are rigidly connected to the frame 1 of the frame 1 remote from the lateral frame members 1b, 1b. rlhe Lbe'ams 7 form guides.

for an elevating member (indicated as an entirety at 8), to whichreference will later be made. rlhe guides 7 extend downwardly below the frame 1 to permit lowering of the elevatingv member 8 "into engagement with or relatively close to the floor, as shown in Fig. 1. The guides 7 extend upwardly to any'desired height, depending upon the conditions to be met with in the operation ofthe truck. The

by a pair of angle plates 7, the walls of which are riveted orothe-rwise secured to the end walls of the guides and the channel. bars 1a, and a pair of tie bars .7b of channel shape in cross section preferably connected at their lower vends to the frame members 1" and at j their upper ends to theV extended ends of brackets 9 secured to and extending inwardly from the upper ends of the guides 7. Y Due to the placement of the motor l() for the elevating member 8 toward one side of the frame 1, one of the tie bars is bent laterally between its ends, as shownrin Figs. 2 and 3.

11 indicates a transverse member secured to the inner side walls 'of the 1-beams 7 below their connection with frame 1 and extending laterally beyond the guides 7 to form an axle for a pair of trailing or supporting wheels 12.

` The transverse member 11 may be cast or otherwise formed. The axle 11 is secured to the inner side walls of the guides 7 by bolts 13 and by bolts 14 connecting lugs 15 (formed integrally with the axle 11) to the ianges or side walls of the beams, or by welding. The

I' opposite ends of the axle 11 are preferably The `outer end 17 of each spindle 16a is formed fashioned or shaped to form knuckles 11a to receive the pintles 16 of the wheelspindles 16a for the wheels 12 (see Fig. 8), whereby the latter may be operated for steering purposes.

with an annular recess 17 a forming a seat for the inner race of an anti-friction bearmg 18, the outer race thereof belng seated 1n an annular recess 19 formed in the hub portion of the adjacent wheel 12. 20 indicates acap for closingthe outer end-of the wheel hub and spindle 16, the perimeter of the cap fitting a recess 21 formed in the face of the hiib and movably secured in such position in any de! sired manner. As shown in Fig. 8, the inner.

4 face of the cap overlaps the outer bearing 18 so as to maintain it in its seat 19; and the in'- ner raceof the bearing is engaged by a collar -e i1d;17 of the spindle 16a.

or nut 22 screw threaded on the outer or free vIn the arrangement above described, it will .be *noted that (l) the axes of the wheels 12 are positioned at the extreme load handling end of the frame, being substantially in line with thecentral longitudinal plane between the gliide walls or flanges ofthe guides 7 so that the weight of the load is carried substanwear/ia tially directly by these wheels and necessity for counterweighting the opposite end of frame is avoided; (2) wheels corresponding in size to the traction wheel 3 may be readily used, thereby permitting of lstandardization of these wheels and their interchangeability for repair purposes; and {3)the wheels may be disposed. in alignment with 'the wheels 3,'so that the over-all width of the truclr will not exceed that ofthe traction wheels or i,

the lateral frame members 1", 1V, making possible to operate the truck with relatively great facility. llt will also be seen that the trailing wheels are supported in a relatively simple manner and that the guides 7 can be spaced relatively far apart since the chamber or space between the side walls of the l-beanis may beutilized to receive the wheels 12,when Yturned for steering purposes (see dotted lines in Fig. 1). To insure ample space and room for the swinging of the wheels 12, the guides 7 f2 are beveled or cut away as `shown at 7 This cut-away will not affect the operation ofthe elevating .member 8 since theup er pair of shoes 8a which engage the front si e walls,

tion when the elevating member isl in its low ermost position4 (see Fig. 4).

. v 99 do not move downwardly to tle cut-away por- 23 indicates a pair of angle bars lixedt the I frame 1 andextending upwardly and downwardly relative thereto. 24: indicates a dash supported by the angle bars. 25 vindicates a;

controller for controlling the 4supply of current to the motor 5. The operating shaft-25 of the controller is connected to ka. vlever 26;

the lever 26 is connected by a rod 2651150 a handle 27, pivoted at 27fuponabraclzet 28 that is supported by the dash 24; 29 indicates a trigger mechanism for locking the handle 27 ed on the dash 24 and its operating mechanism is connected bya rod 30a to the brake mechanism 31. 33 indicates a pair of plates preferably secured to the depending portions of the angle bars 23and supporting brackets 33a in which are mounted the opposite -ends of a shaft 33b pivotally supportmg the plat lao form32, whereby the latter may be .swung upwardly when not in use.l 32a indicates a.`

counterbalance for the platform 32. v

lOf the brake mechanism 31, 31a indicates a` foot pedal fulcrumed on the shaft 33" and connected by a linkage 31h 'with a rod 31, which in turn isfconnected to one arm ofa 'bell-crank .34 pivoted upon a studshfaft 349*vv mounted on the axle casing 4. The other arm of the bell crank is connected through suitable links with oneend of a brake band 35 adapted to engage anddisengage a brake wheel 35n xed to the extended end of the propellershaftV driven by the motor 5. The linkage 311 is so connected with the pedal 311 and rod 31", that the brake band 35 will be the wheel 35a.

one of the frame members and to the rod 31c applied when the pedal 31a is raised, as shown in Fig; 1, so that operation of the pedal downwardly will release the brake band 35 from 36 indicates afsprin'g fixed to and normally acting thereon to apply the brake and to elevate the pedal 31e.v Accordingly, movement of the pedal downwardly will put the spring 36 under tension and upon the release of the pedal the spring will eect operation of the rod '31 and brake band to cause the latter to engage the wheel 35a.

37 indicates as an entirety-steering means for the wheels 3 and 12. Gf these means, 37 a jecting inwardly from the spindles for the wheels 3 and connected by a tie rod 39a.' Y One of the arms 39 is extended and its free end is pivotally connected to one end of a rod 40 eX- tending substantially transversely of the frame 1 and connected at its opposite end to a lever 40a Xed to a rockshaft 41. The rock shaft 41 is mounted inspaced bearings'42 provided at the lower ends of a pair of strips .42'U1 secured to and depending from the frame members 1a. A43 indicates a lever Xedly con nected tothe 'rock shaft 41 and pivotally connected to one end of a rod43a. The rod 43a extends substantially transversely vof the frame 1 and ispivotally connectedat its op'- posite end to the extended end of an arm\44.

The arm44 isiixed in any desired manner to the spindle 16a of the adjacent wheel 12 andby means of a tie rod 44a to the arm'44 ofthe spindle'll3 of the other wheel 12. .Aswill be understood from the foregoing description,- the steering means operate to swing both pairs of wheels simultaneously but in opposite directions and thus enable the truck to be turned in a relatively small area. The arms 40a and 43 are provided with hollow bosses which it the rock shaft 41 and are adjustably clamped thereto by suitable devices 41a. The lbosses are disposed on the rock shaft on the outer sides of the bearings 42 and act thereagainst to prevent endwise movement of the shaft.

45 indicates the batteries for supplying c urrent 'tothe motors 5, 10. The batteries are mounted on the frame members l", 1b', and

preferably near that end of the frame remote from the guides 7 so as to afford mounting space for the motor 10 and themechanism driven thereby. The batteries 45 are preferably enclosed in a casing 45a.

46 indicates a bracket mounted on the dash 24 and supporting a controller 47 which controls thesupply of current to the motor 10 to drive it in either-direction. f

The elevating member 8 may be of any desired construction, but by preference it com# prises a vertical'member 8b guided between the guides 7 and a horizontal load engaging and lift member 8. The vertical member 8b comprises a pair of spaced castings 48 connected in fixed spaced relation by a pair of plates 48a, 48a, the latter being fixed along their lateral edgesbyrivets to the castings 48. The castings48 are provided at their upper and lower ends with angularly disposed bosses which support stud shafts 49 in planes parallel to the inclined inner faces of the side walls of thev I-beams 7, so that the upper pair of rollers 85 may engage the front side walls and the lower pair of rollers 8'l may engage the rear side walls and roll face to face therewith with minimum friction. At their lower front edges the castings 48 are provided with extensions 49` carrying knuckles 49a, which support a transverse sha ft 49, and abutments 49C.` The load engaging and lifting member 8 preferably comprises .a plurality of spaced -arms 50, connected at their inner ends by'a base portion 50a which is ,provided with pairs of up-'standing elejments 5()b carrying pairs of knuckles 50c through which the shaft 49b extends to plvotally connect the member 8c to the vertical member 8b. The lmuckles 50care arranged at opposite sidesof the knuckles 49a so as to co-act therewith to prevent lateral movement of the member 8c on the shaft. By providing the load engaging and lifting member 8c with upstanding elements 50h, itiwill be seen that the arms 50 are supported in a plane below the lower edge of the vertical member 8". Ac-

cordingly the lifting member 8c can be moved downwardly into engagement with the floor, if desired and hence accommodate itself to loads that are supported on relatively low 51 indicates as an entirety the mechanism vfor raising and lowering the elevating member Salong the guides 7. Of this mechanism,

51a. indicatesa pair of spaced standards mounted on anplate 51" supported on the -frame members l? between the battery casing 45a and guides 7. 52 indicates a cradle to which-the motor 10 is rigidly secured. The Cradle 52 is shaped to provide a casing 522t fora `worm gear keyed to .a shaft 53. The

. Aside Walls of the casing 52a are constructed in r permitting thecradle 52 to be inclined asV showniiijFig. l. The armature shaft l or the motoris connected-in any desired man- `ner to a 'shaft 54 supported in bearings pro` vided in a supplemental 'casing 52" which is' fixed to the casing 52a. The shaft 54' is provided with a worm 54a which meshes with the worm gear keyed tothe shaft 53sofa`s to drive' the latter. At one end the shaft 53eX- tends through openings formed in the side `wall of thecasing52:l and adjacent standard. 51a and carries a drum 55 on which wind'sfa'nd .f unwinds a -iexible member 56-such as a 'the weight 60 and serving to prevent movev.ment thereof" upwardly due-to the pull on "'cable 56, by reason of the weight of the elevatcable. The cable 56 is connected to the drum 55 in any desired manner and eXtendsthere-A from. upwardly over or around a.' sheave 57.

' supported at the upper end of the guideslin the manner to be later set forth. From the sheave 57. thejcable extends downwardly Ato and around a sheave 58, carried bythe verti` cal member 8b, and'from thel latter4 sheave.

the cable l56 extends upwardly to and around a sheavev 59 vsupportedat the upper endlof the guides 7. From the sheave 59, the cable 56 extends downwardly, its outer or freeeiid anism indicated as an entirety at 60.

vbeing preferably connected to a take-up niec'hj gaging'any of 'thevsheaves or getting twisted The sheaves 57, 59, are supported on a shaft 6l mounted in bearings 61a which are? providedina cross member61". The cross member 61b is supported at one end by a plate riveted to the front side walls of the I-beams 7 and at its opposite end byA a channel bar 62 Supported at its opposite ends on the brack ets 9. By this arrangement the sheavesA 57,

59, can bearranged relatively close together to bring their outer peripheries in substantial alignment with. the peripheral points at which the cable 56 engages and disengages the sheave 58 as it runs therearound. It also leaves the upper ends of the guides unob- -structed so that the elevating member 8 can be moved' to the eXtreme upper end of the guides. The sheave 58 is provided with hubs rotatably fitting a transverse shaft 63 sup# ported at its opposite ends by the connecting and spacing plates 48, the hubs projecting laterally so as: to engage`- the inner Jfaces of these plates to prevent the endwise movementof the sheave on the shaft.

64 indicates Aasv an entiretyan automatic means for `shutting off current to the motor 10 in the event the elevating member 8'is moved to a redetermined position in eitherdirection. y f these means, 64a indicates a casing enclosing a switch mechanism having a rock shaft 64b to which is connected a lever 64e. The'lever is connected to rods 65, 65, guided in openings formed in brackets '65, and carrying adjustable tappets 65b with l either of which the elevating member 8 engages as it moves in either direction, the lat ter being preferably provided with a projection 66 (see Fig. l) which engages either tappet and through it operates the switch levert 64.

'llie'take-up mechanism 60 preferably comprises a weight a to .which the -outer end of.

the cable 56 is pivotally connected as shown in Figs. 2 and 3. The Weight 60a is slidably mounted in a guide 60b that is fixed to a plate GOCinterposed between the rear side walls of the guides 7 and the angle plates 7 a, such plate forming the inner guide wall for theweight 60 (see Fig. 4). l 67 indicates a pair of bolts extending through and supported inaligned openings formed in the plate 60 and guide 60b and also extendingI through openings in comes-wedged. or engages an obstruction, lthereby causing slack in the cable 56, the elon- {gated openings will permit the` weight to t'gravitate downwardly and thus take up all slack in the cable'. and prevent it from disenon the drum 55. Y

6,78. indicates a connection between the takeup means 60 and the cut-out mechanism 64 for operating the latter when the weight 60a operates to stop the motor. The connection -68 preferablycomprise'sa link 68a pivoted to and depending from the vWeight 60a, a link 68b pivotally vconnected at its opposite ends tothe link 68@ `and a stationary part, for eX- ample vtheA axle 11, and carrying a lugj68c formed with an opening through which the adjacentv rod l extends and a spring 69 coiled around therod and interposed between the lug 68c and a collar 69a adjustably fixed to the rod. yIn operation, the movement 0f the weight 60a downwardly swings the link 68c about its pivotal connection with the axle ll; this movement compresses the spring ,69 which acts through the collar 69il to move the rod 65 downwardly and thev latter operates the switch cutout mechanism Within the casing 64a.

' 70 indicates aspring coiledaround the lower rod`65cand interposed between the adjacent bracket 65LL and collar 69a. When the rod 65 is moved downwardly,-either due to the engagement of the elevating member 8 with the lower tappet 65b or the operation of No claim is `made herein to the take-up mechanism or the combination thereof with a limiting means since such subjects-matter are the invention of Amiel G. Hutzley covered by an application filed by him on the 24th day of June, 1924 (see Letters Patent No. 1,690,681). s

71 indicates as an entirety a brake mechanism for stopping the shaft of the motor and preventing movement thereof when the current thereto is cut off. Of this mechanism,

71"l indicates a collar extending from the upper end ofthe motor casing and provided on its inner wall with screw threads. '72 indicates an annular member having an inwardly extendingv ring 72a provided with screw threads to engage the screw threads on the collar 7la near its outer edge. The annular member 72 and an integral depending wall thereof lare formed with openings to receiveV bolt shanks 7 3 extending from the motor casing, such Shanks being screw threaded on their outer ends to take nuts 7321,'whereby the annular inember is rigidly clamped to the motor casing.

74 indicates a ring seated in an annular groove 7 4a formed in the face of the-annular member 72 near its outer edge and serving as a spacing element between the annular member and a casing member 7.5. The annular member 72 and-casing member 75 are formed A' with pairs of aligned openings 7521 one pair being shown in Fig. 9) to receive. bolts 76.

carrying nuts 7 6a which-when tightenedclamp the casingmember 7 5to the annular member 72 with the ring 74 between them.

77 indicates a disk or plate (preferablyformed from ironor steel for a reason which will-presently appear) disposed between` the annular member 72 and casing member 75 and movable toward and from said members. The central portion of the plate is cut-away to receive the adjacent free end .of the armature shaft 10 and the nut 10n thereon to which reference will later be made. The disk 77 is made of a size and shape to extend radially a distance great-er than the distance from the .axis of the ymotor to the securing bolts 76 so that by forming notches 77a in the edge of the disk the bolts will serve as guides for the disk and prevent it from rotating with the armature shaft 10. 78 indicates a collar keyed to the extended end of the armature shaft 10.

and having a flange 7 8a carrying a plurality of pins 78". 79 indicates a relatively thin annular plate having openingsA toV receive the pins 78b to connect the plate to the flange 78a to cause it to rotate therewith. The openings in the plate 79 are of a size to permit the plate to move upwardly and downwardly on the pins, which serve as guides therefor, removable devices projecting from Athe pins preventing the displacement of the plate. 7 9a indicates coiled springsrsurrounding the pins 78b and disposed between the plate 79 and flange'78a, the springs being arranged to support the plate substantially midway between the flan ge and the free ends of the pins so that it may move thereon upwardly andl downwardly, the springs tending to return the plate to this position if moved downwardly.

80 indicates a spring, preferably of the coiled type, interposed between the casing member 75 and theplate 77 and normally tending to move the latter toward the annular member 72-that is downwardly*to engage the ro` tating plate 79 and to press the latter against -the annular member 72, thereby causing friction between the rotating disk and the stationary faces of the plate 77 and annular member 72 to prevent rotation of the armature shaft l0 or to stop the rotation thereof upon cutting off the current to the motor asr will be later set forth. The outerend of the spring 8( is preferably engaged by the inner end of a cap screw 8l, which is mounted in a screw threaded opening formed in the casing member 75, such cap screw being rotatable, so as to adjust its inner end toward and from the spring 8O so that the tension of the latter may beincreased or decreased as desired. vThe cap screw 81 may be locked in its adjusted position by a nut 81a. v82 indi- Cates one or more-windings mounted within the casing member and adapted to be connected in the motor circuit in series with the motor when the latter is being driven in either direction, such connection being effected by terminals, one of which is shown at ,82a corfnected to a lead 82", forming one'of the leads for the motor circuit. As shown, the windings 82 are disposed above the plate 77 and -when the circuit to the motoris completed,

automatically to release the brake when the motor is started and to permit the application of the brake when the current is cut off, so that the motor cannot continue to run, due to momentum after the circuit is open.

The windings 82 are preferably supported in the casing member 7 5 by a pair of ring shaped members 83, 84', the former being clamped between the ring 74 and the sidewall of the casing member 75, and the-latter being secured to the body portion of the casing vmember by cap screws 85 extending through screw threaded openings formed therein. As shown in Fig. 9 the annular or ring shaped members 83, 84, engage the inner faces of CA f llU4

the windings and sup ort them .within the y constructingthe annular members 83 and 84to engagethe] inner face of the windings`82, I provide: ni air gap between the windingsand the arm ture 77 To increase the friction between opposite faces of the rotating late 79 and end of said frame, anaxle connected to and casing ymember 75.

` vopposin faces of the armature 7 and annulai-'mem er 72, these latter faces may beprovided with annular' bands 86 of suitable ma terial and secured thereto in any suitable- I. manner; for example, by rivets 86a.

It will also beseen from the foregoing description that tbe rotating friction plate 79 *is normally positionedl out of engagement with the annular member 72, so that upon the operation of the electromagnet, the disengagement of they plate from both opposing relatively 4stationary elements will be immediately effected. i

l To accommodate the collar 78 and flange 78a, the armature shaft 10 is extended and provided at its free end with screw threadsA to take 'the nut 101l which serves to maintain the collar 78 on the armature shaft, and theV i the invention. My disclosures and the description herein are purely illustrative and are not intended to be in any sense limiting.

What I claim is:

1. In apparatus of the class described, the combination of a frame, a pair of guidesfor a slidable elevating member, said guides being connected to one end of said frame and extending vertically upwardly and downwardly relative thereto, an axle supported on the rear sides of said guides below said frame thereabovel and therebelow, said members liaving flanges certain of which serve as )guides for a slidable elevating member, a

pair of support-ing wheels for the opposite supported on the inner sides of said members,

the opposite ends of said axle extending beuckles, and a pair of supporting'wheels.

mounted on said knuckles in line with said rst-mentioned pair of wheels and arranged` to swing into the space between the flanges o i said members when the forward portion of either wheel swings inwardly.

4. In apparatus of the class described, the

combination of a frame, a pair of members y f connected to one end of said frame and extending vertically upwardly and downwardly relative thereto, said members having flan es certain of which serve' as guides for a sl1d ablel elevating device, 'an axle supported on the inner sides of said members betweensaid 'frame and the lower free ends of said members, the opposite ends of said axle extending beyond said members and provided with knuckles, a pair of wheels for the opposite end of said frame, a pair of wheels mounted on said knuckles and extending outwardly beyond the sides of said members, said members and knuckles being so related that the forward portion of each wheel swins into the space between the Hanges of theadjacent member when moved inwardly and the lower portion of each member being cut awa to permit maximum swinging movement o the adjacent wheel.

In testimony whereof, I have hereunto subscribed my name.

EDWARD H. REMDE.

and provided with knuckles at its opposite i ends, a pair of wheels for the opposite end of the frame, and a pair of wheels mounted on said knuckles, portions of said guides being cut away to permit swinging of the last mentioned wheels.

2. In apparatus of the class described, the combination `of a frame,a pair of guides for a slidable elevating member, said guides being fixed to one `end of said frame and ex" tending thereabove and therebelow, a pair of traction wheels for theopposite end of said frame, a pair of trailing wheels, an axle coniv nected'to and vsupported by said guides and extendinglaterally to opposite sides thereof and'carrymg said trailing wheels at its opposite ends in line with said first mentioned wheels, said trailing wheels being swingably mounted on the outer ends .of said axle and the front portion of said guides being cut avvayl to 'permit swinging of said trailing w ee s. v 

